circuitpython/shared-module/usb_cdc/Serial.c

164 lines
6.0 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2021 Dan Halbert for Adafruit Industries
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "shared/runtime/interrupt_char.h"
#include "shared-bindings/usb_cdc/Serial.h"
#include "shared-module/usb_cdc/Serial.h"
#include "supervisor/shared/tick.h"
#include "tusb.h"
size_t common_hal_usb_cdc_serial_read(usb_cdc_serial_obj_t *self, uint8_t *data, size_t len, int *errcode) {
const bool wait_forever = self->timeout < 0.0f;
const bool wait_for_timeout = self->timeout > 0.0f;
// Read up to len bytes immediately.
// The number of bytes read will not be larger than what is already in the TinyUSB FIFO.
uint32_t total_num_read = 0;
if (tud_cdc_n_connected(self->idx)) {
total_num_read = tud_cdc_n_read(self->idx, data, len);
}
if (wait_forever || wait_for_timeout) {
// Continue filling the buffer past what we already read.
len -= total_num_read;
data += total_num_read;
// Read more if we have time.
// Use special routine to avoid pulling in uint64-float-compatible math routines.
uint64_t timeout_ms = float_to_uint64(self->timeout * 1000); // Junk value if timeout < 0.
uint64_t start_ticks = supervisor_ticks_ms64();
uint32_t num_read = 0;
while (total_num_read < len &&
(wait_forever || supervisor_ticks_ms64() - start_ticks <= timeout_ms)) {
// Wait for a bit, and check for ctrl-C.
RUN_BACKGROUND_TASKS;
if (mp_hal_is_interrupted()) {
return 0;
}
// Advance buffer pointer and reduce number of bytes that need to be read.
len -= num_read;
data += num_read;
// Try to read another batch of bytes.
if (tud_cdc_n_connected(self->idx)) {
num_read = tud_cdc_n_read(self->idx, data, len);
}
total_num_read += num_read;
}
}
return total_num_read;
}
size_t common_hal_usb_cdc_serial_write(usb_cdc_serial_obj_t *self, const uint8_t *data, size_t len, int *errcode) {
const bool wait_forever = self->write_timeout < 0.0f;
const bool wait_for_timeout = self->write_timeout > 0.0f;
// Write as many bytes as possible immediately.
// The number of bytes written at once will not be larger than what can fit in the TinyUSB FIFO.
uint32_t total_num_written = tud_cdc_n_write(self->idx, data, len);
tud_cdc_n_write_flush(self->idx);
if (wait_forever || wait_for_timeout) {
// Continue writing the rest of the buffer.
len -= total_num_written;
data += total_num_written;
// Write more if we have time.
// Use special routine to avoid pulling in uint64-float-compatible math routines.
uint64_t timeout_ms = float_to_uint64(self->write_timeout * 1000); // Junk value if write_timeout < 0.
uint64_t start_ticks = supervisor_ticks_ms64();
uint32_t num_written = 0;
while (total_num_written < len &&
(wait_forever || supervisor_ticks_ms64() - start_ticks <= timeout_ms)) {
// Wait for a bit, and check for ctrl-C.
RUN_BACKGROUND_TASKS;
if (mp_hal_is_interrupted()) {
return 0;
}
// Advance buffer pointer and reduce number of bytes that need to be written.
len -= num_written;
data += num_written;
// Try to write another batch of bytes.
num_written = tud_cdc_n_write(self->idx, data, len);
tud_cdc_n_write_flush(self->idx);
total_num_written += num_written;
}
}
return total_num_written;
}
uint32_t common_hal_usb_cdc_serial_get_in_waiting(usb_cdc_serial_obj_t *self) {
return tud_cdc_n_available(self->idx);
}
uint32_t common_hal_usb_cdc_serial_get_out_waiting(usb_cdc_serial_obj_t *self) {
// Return number of FIFO bytes currently occupied.
return CFG_TUD_CDC_TX_BUFSIZE - tud_cdc_n_write_available(self->idx);
}
void common_hal_usb_cdc_serial_reset_input_buffer(usb_cdc_serial_obj_t *self) {
tud_cdc_n_read_flush(self->idx);
}
uint32_t common_hal_usb_cdc_serial_reset_output_buffer(usb_cdc_serial_obj_t *self) {
return tud_cdc_n_write_clear(self->idx);
}
uint32_t common_hal_usb_cdc_serial_flush(usb_cdc_serial_obj_t *self) {
return tud_cdc_n_write_flush(self->idx);
}
bool common_hal_usb_cdc_serial_get_connected(usb_cdc_serial_obj_t *self) {
return tud_cdc_n_connected(self->idx);
}
mp_float_t common_hal_usb_cdc_serial_get_timeout(usb_cdc_serial_obj_t *self) {
return self->timeout;
}
void common_hal_usb_cdc_serial_set_timeout(usb_cdc_serial_obj_t *self, mp_float_t timeout) {
self->timeout = timeout;
}
mp_float_t common_hal_usb_cdc_serial_get_write_timeout(usb_cdc_serial_obj_t *self) {
return self->write_timeout;
}
void common_hal_usb_cdc_serial_set_write_timeout(usb_cdc_serial_obj_t *self, mp_float_t write_timeout) {
self->write_timeout = write_timeout;
}